Cuban primes: Difference between revisions

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 with multiple columns, commas and all.
-<lang Common Lisp>;;; Show the first 200 and the 100,000th cuban prime.
+<lang lisp>;;; Show the first 200 and the 100,000th cuban prime.
 ;;; Cuban primes are the difference of 2 consecutive cubes.
 (defun primep (n)
-	(cond ((< n 4) t)
+  (cond ((< n 4) t)
-          ((evenp n) nil)
+        ((evenp n) nil)
-          ((zerop (mod n 3)) nil)
+        ((zerop (mod n 3)) nil)
-          (t (loop for i from 5 upto (isqrt n) by 6
+        (t (loop for i from 5 upto (isqrt n) by 6
-                 when (or
+              when (or
-                          (zerop (mod n i))
+                     (zerop (mod n i))
-                          (zerop (mod n (+ i 2))))
+                     (zerop (mod n (+ i 2))))
-                   return nil
+                return nil
-                 finally (return t)))))
+              finally (return t)))))
 (defun cube (n) (* n n n))
 (defun cuban (n)
-	(loop for i from 1
+  (loop for i from 1
-          for j from 2
+        for j from 2
-          for cube-diff = (- (cube j) (cube i))
+        for cube-diff = (- (cube j) (cube i))
           when (primep cube-diff)
-              collect cube-diff into cuban-primes
+            collect cube-diff into cuban-primes
-              and count i into counter
+            and count i into counter
-          when (equal counter n)
+          when (= counter n)
-              return cuban-primes))
+            return cuban-primes))